Willamette valley, Oregon... no wind since 1963.

It has a Rohn label... just no part number... it will work fine from what has been said,  thanks very much.

Tom

Yes, I think it does look mostly like those units in the Rohn site.   It just seems a little 'flimsy' for free standing and that is why I asked.  At the base I expected pretty good size bolt holes but found on a pair of 1/4" holes in each foot... seemed a little light for free standing.

My use is only as a distant support for a long wire antenna and it would only be vertically weight loaded and quite lightly.  I plan to put a pulley in the top of the tower for the antenna support line to travel through then on to the old cherry tree at 45 degrees with a counter weight there.  Should be OK but side wind loads would be the issue I worried most about.

I guess trying it and making sure the lateral fall line is clear of anything like plants that the wife wants to keep is then all there is to worry about.

Thanks, Tom

I acquired an old Rohn tower. It has four sections that are eight feet in length. And the bottom section has legs that splay out to a triangle about two feet on a side.  

It has a Rohn label but no model number.

My question is, since I don't see guy points that have been used, is it possible to free stand it?   Of course on a concrete base.

Tom

OK!  I have made contact!!!.... It was my dyslexia that caused some of the confusion... the plate is actually KL7IAK and the fellows name is easy to locate, Terry White.

It is still interesting how ham radio often ties many things together.  But he, of course, was not on Shemya so the "uncle" thing is not there...

However, in talking to him I learned that he had once lived in the local area ('50's) and had at least two other call signs including K7AUK and at one time a "V" call in India while stationed there with something like foreign service.

My original hope was only to make contact and invite him to our local "ham" gathering that we have once a month.  We get up to 20 amateurs to show up most months but the more the better.

In talking to him it turns out he knows one of the stalwarts of our group from 1950's field days so it will be a good ragchew at the next get together!

In addition, when he was in India he mentioned he maintained a bank of 30 R-390a's for the US consulate and I happen to be currently rebuilding one on my bench at home and am excited to have the potential for a "professional" come over to give me some pointers!

If that wasn't enough I see from the internet he was involved with some kind of spectrum analyzer development in the past.  My elmer, W7JIP, was developer of spectrum analyzers for Tektronix and it has always left me with an interest in that equipment so we will have even more to "discuss" at the ham breakfast.

This is probably more than anyone wanted to know but because I started this with an erroneous license plate "read" I felt it warranted some explanation.

73, Tom 

Don't give up.... I will tackle him at next sighting!  Turns out my wife's uncle was on Shemya in or around the same time.  Post WW2. Tom

Thanks, I will try to see if that name is in local phone book.
The plate is an earlier version of an Oregon plate (solid yellow) but he could have just kept the vanity plate... there is more to this story. If I can make contact I will let you know.

73

A local car I see around town bears plate KL7AIK and I am unable to find out his name so I can invite him to local ham gathering.  I am guessing he has lapsed with the FCC.  Any hope of getting a name short of chasing him down?

Thanks

The transistor you specify is not one I seem to have.  Is there a different manufacturers equivalent part number?

I have a lot of 2N5591's and similar but I think too low power for your application?

T

The IF transformers are relatively easy to deal with I ended up replacing a couple and found it easy... just make sure and position the attached circuitry in as close as possible to original location.  I ended up with a donor set and that helped a lot as well.

Tom

Be very careful of moving any wires that run in the vicinity of the IF cans.  Particularly tube plate supply wires.  The less you disturb the wires the less chance of generating feedback issues like I did with mine... took a long time to sort it out.  The malady shows up as a squeal at high RF gain settings.. can even be band specific.  Good radio once restored... 73 Tom

Well I am encouraged by the responses.... I think first I will catalog what there is and after hearning you folks suggestions, I won't just toss them... not that I could really have done that anyway....

Maybe use Xcell for a spreadsheet....

Probably rather find a good home for them than anything else.

Thanks for the help, 73, Tom

Just recently an older local ham died and I "inherited" most of his stuff.  I guess I was surprised by the quantities of some of the items.  He had a huge organized selection of resistors but they were all from the 1950's and earlier and on checking them they turn out to have very disparate values from their markings. 

However, I found a large box of plastic organizers filled with carefully identified transistors (5, 10, or sometimes 20 in a bin).  Probably a thousand or more and each bin clearly labeled.

I know most are of little value but I did notice several bins with RF power transistors.  Ones like Motorola 2N5591, etc. 

Do any of you "homebrewers" have any idea if those are of any interest anymore?  Or, have they gone the way of tubes already?

Just curious, 73, Tom

Couldn't you get a lot of information with a oscilloscope? It seems like first you might need some "standard"data for the different types of microphones.  Just a thought.

Very helpful...  I think what is going on is that I have never in the past "experimented" quite as much with AM modulation, nor have I ever had all the equipment and time needed to look at a trapezoid pattern.  I recently retired and now have the time to get more involved with the transmitters and receivers. I am very interested in producing quality signals though so learning how to identify problems and solve them is my greatest interest as the hobby continues.  I appreciate you folks very much, thanks.  Tom

W8JI, thanks for the very helpful reply.  It sounds like I need to take the "audio" at the input of the modulator, right after the microphone. Then if that looks OK, I move along the modulator stages checking as I go.

If the source of any distortion is microphone induced then I can start with my recently acquired HP-200AB as a signal source rather than the microphone?

This brings up another 'worry' and that is that the HP has a 600 ohm output impedance and the modulator has a fairly high input impedance, would I need to make some kind of matching network so as to not distort the waveform if I use the HP for a good sine wave source?

And finally, does it make any sense to attach a speaker to the HP and simply hold it near the microphone at nominal audio level and see what the trapezoid looks like then?

I know it is a lot of questions but appreciate any thoughts, 73, Tom